1. Field of the Invention
The present invention relates to a steering column for a vehicle. More particularly, it relates to a steering column for vehicle that allows impact absorbing member to absorb an impact that is generated when an adjusting bolt collides with tilting guide hole or telescoping guide hole during a tilt or telescoping operation, thereby improving the operational feeling and reducing operational noise.
2. Description of the Prior Art
In general, a steering column for a vehicle is an apparatus that surrounds a steering shaft for transmitting a rotational force that is generated through the manipulation of the steering wheel by the driver to a rack and pinion mechanism in order to support the rotation of the steering shaft. The steering column is coupled to the body shell through a bracket to fix the location of the steering shaft.
A telescoping or tilting function may be added to the steering column for the convenience of the driver, in which the tilting apparatus is an apparatus for adjusting the fixing angle of the steering wheel. The telescoping apparatus is formed by mounting two hollow pipes such that the steering column may be extended and contracted axially. When the vehicle experiences a collision, the steering shaft and the steering column collapse in order to absorb impact energy.
Accordingly, the steering apparatus may be classified into telescoping and tilting steering apparatuses according to the functions, and a tilting function may be added to a telescoping steering apparatus according to occasions. The driver can smoothly manipulate the steering operation by adjusting the protrusion degree or the inclination angle of the steering wheel in correspondence to the height or body shape of the driver through the functions.
FIG. 1 is an exploded perspective view of a part of a steering column for a vehicle according to the related art.
As illustrated in FIG. 1, the steering column 100 for a vehicle, according to the related art, includes: an outer tube 101 in which a steering shaft 175 is accommodated; an inner tube 170 inserted lots; the outer tube 101; a lower mounting bracket 165 installed in the inner tube 170 and fixed to the body shell; an upper mounting bracket 105 installed on the upper side of the outer tube 101 and fixed to the body shell; a distance bracket 180 coupled to the outer tube 101 and having a telescoping hole 185; a plate bracket 150 formed integrally with the upper mounting bracket 105 and having a long tilting slot 110; a telescoping fixed gear 181 provided on an outer surface of the distance bracket 180; a tilting fixed gear 145 provided on an outer surface of the plate bracket 150; a movable gear block 129 including a telescoping actuating gear 162 that is engaged with or separated from the telescoping fixed gear 181 and a tilting actuating gear 140 that is engaged with or separated from the tilting fixed gear 145; a cam 135 coupled to the movable gear block 129; an adjusting bolt 130 that passes through the telescoping slot 185 and the tilting slot 110 in order to pass through the movable gear block 129 and an adjusting lever 115; a nut 120 coupled to the adjusting bolt 130 such that the movable gear block 129 and the adjusting lever 115 may be fixed; springs interposed between the actuating gears 140 and 180 and the movable gear block 129; and a washer 125 interposed between the adjusting lever 115 and the nut 120.
The tilting and telescoping operations are applied by fastening and releasing the adjusting lever 115, and are achieved by the principle stating that if the adjusting lever 115 is fastened, the plate bracket 150 is narrowed to apply a pressing force to the outer tube 101 such that the outer tube 101 and the inner tube 170 are attached to each other by the pressing force, disenabling a tilting operation and a telescoping operation, and in contrast, if the adjusting lever 115 is released, the pressing force between the outer tube 101 and the inner tube 170 disappears, allowing a tilting or telescoping operation.
The telescoping operation is completed by releasing the adjusting lever 115, changing the location of the adjusting bolt 130 along the telescoping slot 185 formed in the distance bracket 180, and fastening the adjusting lever 115.
The tilting operation is completed by releasing the adjusting lever 115, changing the location of the adjusting bolt 130 along the tilting slot 110, and fastening the adjusting lever 115.
When the adjusting lever 115 is locked, the outer tube 101, the steering shaft 115, and the like are fixed, but if the adjusting lever 115 is released, the outer tube 101, the inner tube 170, and the like are tilted with respect to a tilting center 160 by the cam 135, or the steering column is extended or contracted axially.
However, the steering column for a vehicle, according to the related art, generates operational noise due to an impact generated when the adjusting bolt collides with the tilting guide hole or the telescoping guide hole during a tilting or telescoping operation.